Precis: Designing and demonstrating an experiment that shows the risk of airborne transmission of COVID-19 between patients having visual fields analyzed is low. Purpose: The aim was to investigate the possibility of airborne transmission of COVID-19 during Humphrey visual field testing in a real-world scenario. Methods: A particle counter was placed within the bowl of Humphrey visual field analyzer (HFA) before and after turning on the machine to ascertain the effect of the air current produced by the ventilation system on aerosols. A second experiment was run where the particle counter was placed in the bowl and recorded particulates, in the air, as a 24-2 SITA standard was performed by a mock patient and then again immediately after the patient had moved away. We measured aerosol particle counts sized ≤0.3 μm, >0.3≤0.5 μm, >0.5≤1 μm, >1≤2.5 μm, >2.5≤5 μm, and >5≤10 μm. Results: Particulates of all sizes were shown to be significantly reduced within the bowl after turning the machine on, demonstrating that the air current produced by the HFA pushes air out of the bowl and it cannot stagnate. There was no significant difference in measurement of aerosol while there was a patient performing the test and immediately after they had moved away, suggesting that aerosols breathed out by the patient are not able to remain in suspension in the bowl because of the ventilation current. Conclusion: There is no significant difference between aerosol count in the bowl of a HFA before, during and after testing. This suggests the risk of airborne transmission of COVID-19 is low between subsequent patients. This is in keeping with manufacturer’s guidance on Humphrey visual field testing.

Aerosol sized less than 10 μm is not produced during phacoemulsification of human crystalline lens. A mobile laminar air flow machine significantly reduced the number of particles sized 10 μm or lesser within the surgical field.

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In order to maintain manual dexterity and surgical skills, trainees are encouraged to partake in regular simulation. Current options for intraocular surgical simulation require specialist microscopic equipment which is expensive and requires access to simulation facilities. A set of core simulation exercises and basic surgical skills of performing the corneal incisions, capsulorhexis, improving the manual dexterity, and suturing were identified, discussed, and agreed among authors before designing this simulation exercise. In this paper, we propose a smartphone-based, low-cost, low-tech model with corresponding exercises for intraocular simulation that can be used at home for the above-mentioned surgical skill set. This model provides an easy, portable, and reproducible method of simulation and can serve as an adjunct to patient-facing surgical training, especially in the current pandemic, where the excess to the simulation facilities or setup of these facilities may be difficult.

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Background/Aims  Cytomegalovirus (CMV) retinitis is one of the most common opportunistic ocular infections and has traditionally been associated with immunocompromised individuals. We present a case of CMV retinitis following 3 months of treatment with tofacitinib in conjunction with methotrexate (MTX) for rheumatoid arthritis (RA) in an elderly lady with no other co-morbidities. Methods  The case is presented below. Results  69-year-old lady with long standing seronegative, anti-cyclic citrullinated peptide negative, erosive RA since 2016. She was intolerant of sulphasalazine, leflunamide, methotrexate and etanercept. Hydroxychloroquine was avoided due to idiopathic cystoid macular oedema in the right eye with a baseline visual acuity of 6/18. Baseline fundus fluorescein angiogram (FFA) was negative for any vascular, inflammatory or occlusive disease. She was escalated to tofacitinib in August 2019. Approximately 3 months later, she noticed significantly reduced vision in her right eye from 6/18 down to 6/60. She had an FFA and Indocyanine Green Angiography, which showed quite extensive retinal ischaemia and vasculitis. Her bloods revealed a raised serum ACE and a T-spot test from 2018 was reactive followed by a repeat in 2019 which was equivocal. Tofacitinib was discontinued. She was commenced on rifampicin and isoniazid as 3 months prophylaxis for latent tuberculosis (LTBI). Additionally, she was started on oral prednisolone 60mg daily for presumed sarcoid related retinal vasculitis. She failed to improve despite a week’s treatment and subsequently had a vitreous aspirate which was strongly positive for CMV PCR. Her CMV viral load was 267copies/ml. The aspirate was negative for other infectious agents. She was commenced on valganciclovir for CMV retinitis. Unfortunately, her vision remained unchanged despite the viral load becoming undetectable a few weeks later. Despite having LTBI, there was no reactivation of this with her immunosuppressive therapy. Conclusion  CMV retinitis is usually associated with immunocompromised individuals and is rarely encountered related to tofacitinib therapy for rheumatoid arthritis. Tofacitinib suppresses T cell function by inhibiting STAT signalling pathways, modulating T cell activation and cytokine production. Our case highlights the preferential development of CMV retinitis over active TB in the presence of LTBI, which is a recognised risk with the use of JAK kinase inhibitors. TB risk has been associated with genetic mutations in IL-12, IFN-γ and STAT1 pathways while CMV activation may be influenced by mutations in HLA ,Toll-like receptors, immunoglobulin light chain antibodies, IFN lambda region as well as alternative transcripts of the CMV viral major immediate early genes. Disclosure  K. Beharry: None. S. Kaur: None. E. Papagiannuli: None. S. Moses: None. D. De Lord: None.